Research Article
Preoperative Factors and Early Complications Associated With Hemiarthroplasty and Total Hip Arthroplasty for Displaced Femoral Neck Fractures
Geriatric Orthopaedic Surgery & Rehabilitation 2014, Vol. 5(2) 73-81 ª The Author(s) 2014 Reprints and permission: sagepub.com/journalsPermissions.nav DOI: 10.1177/2151458514528951 gos.sagepub.com
Christopher P. Miller, MD, MHS1, Rafael A. Buerba, BA1, and Michael P. Leslie, DO1
Abstract Displaced femoral neck fractures are common injuries in the elderly individuals. There is controversy about the best treatment with regard to total hip arthroplasty (THA) versus hemiarthroplasty. This study uses the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database to evaluate the preoperative risk factors associated with the decision to perform THA over hemiarthroplasty. We also evaluate the risk factors associated with postoperative complications after each procedure. Patients older than 50 years undergoing hemiarthroplasty or THA after fracture in the NSQIP database from 2007 to 2010 were compared to each other in terms of preoperative medical conditions, postoperative complications, and length of stay. Multivariate logistic regression models were used to adjust for preoperative risk factors for undergoing a THA versus a hemiarthroplasty and for complications after each procedure. In all, 783 patients underwent hemiarthroplasty and 419 underwent THA for fracture. Hemiarthroplasty patients had longer hospital stays. On multivariate logistic regression, the only significant predictor for having a THA after fracture over hemiarthroplasty was being aged 50 to 64 years. The patient characteristics/comorbidities that favored having a hemiarthroplasty were age >80 years, hemiplegia, being underweight, having a dependent functional status, being on dialysis, and having an early surgery. High body mass index, American Society of Anesthesiologists (ASA) class, gender, and other comorbidities were not predictors of having one procedure over another. Disseminated cancer and diabetes were predictive of complications after THA while being overweight, obese I, or a smoker were protective. High ASA class and do-not-resuscitate status were significant predictors of complications after a hemiarthroplasty. This study identified clinical factors influencing surgeons toward performing either THA or hemiarthroplasty for elderly patients after femoral neck fractures. Younger, healthier patients were more likely to receive THA. Patients particularly at higher risks of complications after hemiarthroplasty should be monitored closely. Keywords fragility fractures, adult reconstructive surgery, geriatric medicine, geriatric trauma, trauma surgery
Introduction Hip fractures are common orthopedic injuries in the elderly individuals. In 1996, approximately 340 000 hip fractures occurred in the United States, most often among women aged more than 65 years.1 Caring for patients following a hip fracture presents an increasing burden not only on our health care system but also on the patients themselves as these injuries represent a life-changing event that has a 20% to 30% 1-year mortality rate.2-4 Additionally, the average lifetime cost incurred by sustaining a hip fracture is as high as US$81 300 of which US$19 937 is incurred at the initial hospitalization and the remainder from subsequent long-term care in nursing homes and lost wages and productivity of the patient’s family.2,5-7
Although the standard treatment algorithm for extracapsular, intertrochanteric hip fractures is well accepted, the treatment for intracapsular femoral neck fractures is more controversial.8 Femoral neck fractures in elderly individuals are commonly classified according to the Garden classification. Nondisplaced fractures (Garden I and II) are usually 1
Department of Orthopaedics and Rehabilitation, Yale University School of Medicine, New Haven, CT, USA Corresponding Author: Christopher P. Miller, Department of Orthopaedics and Rehabilitation, Yale University School of Medicine, 800 Howard Ave, First Floor, New Haven, CT, 06520, USA. Email: [email protected]
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Geriatric Orthopaedic Surgery & Rehabilitation 5(2)
treated with hip preservation, and displaced fractures (Garden III and IV) are generally treated with arthroplasty in elderly patients.9 The primary indication for arthroplasty in patients with displaced femoral neck fractures is to avoid fracture nonunion and avascular necrosis in patients treated with internal fixation, which has been reported to be as high as 39%.10,11 Many surgeons prefer to treat displaced femoral neck fractures with a hemiarthroplasty, particularly in very elderly patients.8 However, numerous studies have been published demonstrating that functional outcomes, walking distance, self-reported pain scores, and hip disability indices are superior for patients treated with a total hip arthroplasty (THA) as compared to hemiarthroplasty.11-19 It has similarly been shown that although hemiarthroplasty is less expensive in the short term, total hip replacement is generally more cost effective in the long term due to the lower revision rates.10,11,20 In contrast, the complexities of performing a total hip replacement for femoral neck fracture include an increased rate of dislocation, longer operative times, greater blood loss, and a more technically demanding operation.8,11-14,17-19 As detailed earlier, there have been numerous studies evaluating the long-term outcomes following THA and hemiarthroplasty after a femoral neck fracture. However, one aspect that is missing from the literature is an evaluation of the preoperative factors that influence the choice to perform either a hemiarthroplasty or a total hip replacement. The American College of Surgeons National Surgical Quality Improvement Project (ACS NSQIP) database collects data from multiple centers about preoperative patient characteristics and short-term postoperative complications. Using this database, we sought to (1) evaluate the preoperative factors associated with the decision to treat patients with a total hip replacement or hemiarthroplasty and (2) compare which preoperative factors were associated with complications following these 2 surgeries.
Materials and Methods Data Source The ACS NSQIP is a prospective, risk-adjusted, multiinstitutional outcomes program. The details of data collection strategies, inclusion criteria, sampling procedures, and outcomes measured in the ACS NSQIP have been reported.21-23 The ACS NSQIP collects data from 258 medium-to largesized private hospitals in the entire United States in both the inpatient and the outpatient settings. Hospitals in the ACS NSQIP need to submit 1 680 cases per year and must hire at least 1 full-time surgical clinical reviewer to collect the data. The data collected consist of 135 HIPAA (Health Insurance Portability and Accountability Act)-compliant variables, including preoperative comorbidities, intraoperative variables, and 30-day postoperative morbidity, and mortality outcomes for patients undergoing major surgical procedures. The ACS NSQIP data from 2007 to 2010 were utilized. Using Current Procedural Terminology (CPT) codes, we
identified all patients who underwent hemiarthroplasty or THA. We then cross-referenced these CPT codes with the International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code listed for each patient to determine whether the procedure was performed in a setting of fracture. Patients with additional CPT codes were excluded from the analysis, indicating they underwent a second unrelated procedure (ie, humerus repair, arthroscopy of knee, vascular procedures, etc) under the same anesthetic period. We also excluded patients who had CPT codes indicating the hip arthroplasty procedure was secondary to removal of a bone tumor as well as patients who were 10% weight loss in the last 6 months, or renal failure were not predictive of having a complication after either a hemiarthroplasty or a THA (data not illustrated).
Results A total of 783 patients underwent hemiarthroplasty and 419 patients underwent THA for fracture. Differences in patient demographic and clinical characteristics and comorbidities by arthroplasty procedure are shown in Tables 1 and 2, respectively. Compared to the hemiarthroplasty patients, patients undergoing THA were more likely to be men, younger (age 50-64 years), functionally independent in their activities of daily living, have a higher BMI (overweight or obese class I-III), and have a lower ASA class but less likely to have early surgery (all P < .05). The THA patients were more likely to smoke, drink alcohol, and be on chronic corticosteroids but less likely than hemiarthroplasty patients to be on dialysis, have had a stroke with neurological deficits, be hemiplegic, or have an open wound/wound infection, bleeding disorder, impaired sensorium, or DNR status (all P < .05).
Unadjusted Outcomes Compared to the patient group who underwent hemiarthroplasty, the patients who underwent THA for fracture were more likely to have received a blood transfusion (14.4% vs 22.7%, P < .01) but less likely to have had one or more complication (excluding blood transfusion) overall (18.9% vs 13.6%, P < .05) as shown in Table 3. Patients undergoing THA had on average shorter lengths of hospitalization compared to hemiarthroplasty patients (mean LOS ¼ 5.48 days vs 7.03 days, respectively; mean LOS difference 1.55 days (95% CI: 1.001-2.101 days); P < .001.
Discussion Hip fractures are common problems that are already challenging the medical system as the population ages.1-4,24 These fractures come in many varieties and levels of complexity but one of the most common types is a displaced femoral neck fracture. Recently, a number of studies have shown that THA has improved outcomes over hemiarthroplasty.11-19 The goal of this study was not to demonstrate the superiority of total hip replacement but to identify which preoperative factors may be associated with the decision to perform THA versus hemiarthroplasty and to compare the complications associated with each. Using the multivariate model, we identified 6 factors associated with the decision to perform THA or a hemiarthroplasty including age, BMI, functional status, dialysis, hemiplegia, and early surgery (Figure 1). These comorbidities reflect a more medically complex patient pool. A large number of patients who have a femoral neck fracture are elderly patients with significant comorbidities who are not physically active. As such, a hemiarthroplasty will likely work well and the proposed increase in function associated with a THA may not be realized by many of these patients. Also of consideration when deciding between hemiarthroplasty and THA is the high mortality rate within 1 year of hip fracture, the increased rates of dislocation after a total hip, and the cost of the prostheses.2-4,8,11-14,17-19 In patients who are at high risk of subsequent falls, a
Downloaded from gos.sagepub.com at UNIV OF CONNECTICUT on June 7, 2015
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Geriatric Orthopaedic Surgery & Rehabilitation 5(2)
Table 1. Demographic and Clinical Characteristics of Patients Undergoing Hemiarthroplasty Versus Total Hip Arthroplasty for Fracture.a,b,c Procedure Demographic and Clinical Characteristics
Hemiarthroplasty, n ¼ 783
Total Hip Arthroplasty for Fracture, n ¼ 419
Gender, % Women Men Race, % White Black Hispanic Other Unknown Age group, % 50-64 65-79 80 BMI, % Underweight (
Preoperative Factors and Early Complications Associated With Hemiarthroplasty and Total Hip Arthroplasty for Displaced Femoral Neck Fractures
Geriatric Orthopaedic Surgery & Rehabilitation 2014, Vol. 5(2) 73-81 ª The Author(s) 2014 Reprints and permission: sagepub.com/journalsPermissions.nav DOI: 10.1177/2151458514528951 gos.sagepub.com
Christopher P. Miller, MD, MHS1, Rafael A. Buerba, BA1, and Michael P. Leslie, DO1
Abstract Displaced femoral neck fractures are common injuries in the elderly individuals. There is controversy about the best treatment with regard to total hip arthroplasty (THA) versus hemiarthroplasty. This study uses the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database to evaluate the preoperative risk factors associated with the decision to perform THA over hemiarthroplasty. We also evaluate the risk factors associated with postoperative complications after each procedure. Patients older than 50 years undergoing hemiarthroplasty or THA after fracture in the NSQIP database from 2007 to 2010 were compared to each other in terms of preoperative medical conditions, postoperative complications, and length of stay. Multivariate logistic regression models were used to adjust for preoperative risk factors for undergoing a THA versus a hemiarthroplasty and for complications after each procedure. In all, 783 patients underwent hemiarthroplasty and 419 underwent THA for fracture. Hemiarthroplasty patients had longer hospital stays. On multivariate logistic regression, the only significant predictor for having a THA after fracture over hemiarthroplasty was being aged 50 to 64 years. The patient characteristics/comorbidities that favored having a hemiarthroplasty were age >80 years, hemiplegia, being underweight, having a dependent functional status, being on dialysis, and having an early surgery. High body mass index, American Society of Anesthesiologists (ASA) class, gender, and other comorbidities were not predictors of having one procedure over another. Disseminated cancer and diabetes were predictive of complications after THA while being overweight, obese I, or a smoker were protective. High ASA class and do-not-resuscitate status were significant predictors of complications after a hemiarthroplasty. This study identified clinical factors influencing surgeons toward performing either THA or hemiarthroplasty for elderly patients after femoral neck fractures. Younger, healthier patients were more likely to receive THA. Patients particularly at higher risks of complications after hemiarthroplasty should be monitored closely. Keywords fragility fractures, adult reconstructive surgery, geriatric medicine, geriatric trauma, trauma surgery
Introduction Hip fractures are common orthopedic injuries in the elderly individuals. In 1996, approximately 340 000 hip fractures occurred in the United States, most often among women aged more than 65 years.1 Caring for patients following a hip fracture presents an increasing burden not only on our health care system but also on the patients themselves as these injuries represent a life-changing event that has a 20% to 30% 1-year mortality rate.2-4 Additionally, the average lifetime cost incurred by sustaining a hip fracture is as high as US$81 300 of which US$19 937 is incurred at the initial hospitalization and the remainder from subsequent long-term care in nursing homes and lost wages and productivity of the patient’s family.2,5-7
Although the standard treatment algorithm for extracapsular, intertrochanteric hip fractures is well accepted, the treatment for intracapsular femoral neck fractures is more controversial.8 Femoral neck fractures in elderly individuals are commonly classified according to the Garden classification. Nondisplaced fractures (Garden I and II) are usually 1
Department of Orthopaedics and Rehabilitation, Yale University School of Medicine, New Haven, CT, USA Corresponding Author: Christopher P. Miller, Department of Orthopaedics and Rehabilitation, Yale University School of Medicine, 800 Howard Ave, First Floor, New Haven, CT, 06520, USA. Email: [email protected]
Downloaded from gos.sagepub.com at UNIV OF CONNECTICUT on June 7, 2015
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Geriatric Orthopaedic Surgery & Rehabilitation 5(2)
treated with hip preservation, and displaced fractures (Garden III and IV) are generally treated with arthroplasty in elderly patients.9 The primary indication for arthroplasty in patients with displaced femoral neck fractures is to avoid fracture nonunion and avascular necrosis in patients treated with internal fixation, which has been reported to be as high as 39%.10,11 Many surgeons prefer to treat displaced femoral neck fractures with a hemiarthroplasty, particularly in very elderly patients.8 However, numerous studies have been published demonstrating that functional outcomes, walking distance, self-reported pain scores, and hip disability indices are superior for patients treated with a total hip arthroplasty (THA) as compared to hemiarthroplasty.11-19 It has similarly been shown that although hemiarthroplasty is less expensive in the short term, total hip replacement is generally more cost effective in the long term due to the lower revision rates.10,11,20 In contrast, the complexities of performing a total hip replacement for femoral neck fracture include an increased rate of dislocation, longer operative times, greater blood loss, and a more technically demanding operation.8,11-14,17-19 As detailed earlier, there have been numerous studies evaluating the long-term outcomes following THA and hemiarthroplasty after a femoral neck fracture. However, one aspect that is missing from the literature is an evaluation of the preoperative factors that influence the choice to perform either a hemiarthroplasty or a total hip replacement. The American College of Surgeons National Surgical Quality Improvement Project (ACS NSQIP) database collects data from multiple centers about preoperative patient characteristics and short-term postoperative complications. Using this database, we sought to (1) evaluate the preoperative factors associated with the decision to treat patients with a total hip replacement or hemiarthroplasty and (2) compare which preoperative factors were associated with complications following these 2 surgeries.
Materials and Methods Data Source The ACS NSQIP is a prospective, risk-adjusted, multiinstitutional outcomes program. The details of data collection strategies, inclusion criteria, sampling procedures, and outcomes measured in the ACS NSQIP have been reported.21-23 The ACS NSQIP collects data from 258 medium-to largesized private hospitals in the entire United States in both the inpatient and the outpatient settings. Hospitals in the ACS NSQIP need to submit 1 680 cases per year and must hire at least 1 full-time surgical clinical reviewer to collect the data. The data collected consist of 135 HIPAA (Health Insurance Portability and Accountability Act)-compliant variables, including preoperative comorbidities, intraoperative variables, and 30-day postoperative morbidity, and mortality outcomes for patients undergoing major surgical procedures. The ACS NSQIP data from 2007 to 2010 were utilized. Using Current Procedural Terminology (CPT) codes, we
identified all patients who underwent hemiarthroplasty or THA. We then cross-referenced these CPT codes with the International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code listed for each patient to determine whether the procedure was performed in a setting of fracture. Patients with additional CPT codes were excluded from the analysis, indicating they underwent a second unrelated procedure (ie, humerus repair, arthroscopy of knee, vascular procedures, etc) under the same anesthetic period. We also excluded patients who had CPT codes indicating the hip arthroplasty procedure was secondary to removal of a bone tumor as well as patients who were 10% weight loss in the last 6 months, or renal failure were not predictive of having a complication after either a hemiarthroplasty or a THA (data not illustrated).
Results A total of 783 patients underwent hemiarthroplasty and 419 patients underwent THA for fracture. Differences in patient demographic and clinical characteristics and comorbidities by arthroplasty procedure are shown in Tables 1 and 2, respectively. Compared to the hemiarthroplasty patients, patients undergoing THA were more likely to be men, younger (age 50-64 years), functionally independent in their activities of daily living, have a higher BMI (overweight or obese class I-III), and have a lower ASA class but less likely to have early surgery (all P < .05). The THA patients were more likely to smoke, drink alcohol, and be on chronic corticosteroids but less likely than hemiarthroplasty patients to be on dialysis, have had a stroke with neurological deficits, be hemiplegic, or have an open wound/wound infection, bleeding disorder, impaired sensorium, or DNR status (all P < .05).
Unadjusted Outcomes Compared to the patient group who underwent hemiarthroplasty, the patients who underwent THA for fracture were more likely to have received a blood transfusion (14.4% vs 22.7%, P < .01) but less likely to have had one or more complication (excluding blood transfusion) overall (18.9% vs 13.6%, P < .05) as shown in Table 3. Patients undergoing THA had on average shorter lengths of hospitalization compared to hemiarthroplasty patients (mean LOS ¼ 5.48 days vs 7.03 days, respectively; mean LOS difference 1.55 days (95% CI: 1.001-2.101 days); P < .001.
Discussion Hip fractures are common problems that are already challenging the medical system as the population ages.1-4,24 These fractures come in many varieties and levels of complexity but one of the most common types is a displaced femoral neck fracture. Recently, a number of studies have shown that THA has improved outcomes over hemiarthroplasty.11-19 The goal of this study was not to demonstrate the superiority of total hip replacement but to identify which preoperative factors may be associated with the decision to perform THA versus hemiarthroplasty and to compare the complications associated with each. Using the multivariate model, we identified 6 factors associated with the decision to perform THA or a hemiarthroplasty including age, BMI, functional status, dialysis, hemiplegia, and early surgery (Figure 1). These comorbidities reflect a more medically complex patient pool. A large number of patients who have a femoral neck fracture are elderly patients with significant comorbidities who are not physically active. As such, a hemiarthroplasty will likely work well and the proposed increase in function associated with a THA may not be realized by many of these patients. Also of consideration when deciding between hemiarthroplasty and THA is the high mortality rate within 1 year of hip fracture, the increased rates of dislocation after a total hip, and the cost of the prostheses.2-4,8,11-14,17-19 In patients who are at high risk of subsequent falls, a
Downloaded from gos.sagepub.com at UNIV OF CONNECTICUT on June 7, 2015
76
Geriatric Orthopaedic Surgery & Rehabilitation 5(2)
Table 1. Demographic and Clinical Characteristics of Patients Undergoing Hemiarthroplasty Versus Total Hip Arthroplasty for Fracture.a,b,c Procedure Demographic and Clinical Characteristics
Hemiarthroplasty, n ¼ 783
Total Hip Arthroplasty for Fracture, n ¼ 419
Gender, % Women Men Race, % White Black Hispanic Other Unknown Age group, % 50-64 65-79 80 BMI, % Underweight (
